Breaking news

Tiny dogs, mighty Middle Eastern origins

Researchers say the study findings may be useful for dog breeders. (File photo)

It may be hard to believe, but it's likely the tiny chihuahua is a descendent of the Middle Eastern grey wolf.

Researchers from the University of California, Los Angeles have discovered that a gene found in all small dogs is closely related to one found in wolves in the Middle East.

The team took samples from grey wolf populations around the world and compared their genetic markers to those in small and large dogs to find the link.

Earlier research had found that all small dogs carry the IGF1 gene, which controls their body size.

One of the study's leaders, Dr Melissa Gray, says there was a striking similarity between the gene variant found in small dogs and the variant found in the Middle Eastern grey wolf.

"We have had some other studies that have pointed to the Middle East as being involved in either domestication or body size," she said.

"For instance archaeological evidence has found that there are remains of small dogs in this region. So it's one of the first regions that has been identified with small dogs."

Those remains are dated back about 12,000 years.

Digs in Europe have found remains from 31,000 years ago, but they are from larger dogs.

It remains unclear exactly how or why wolves were domesticated, but Dr Gray thinks people may have adopted smaller wolves because they were easier to house.

"The grey wolves might have started coming around communities of people and raiding their trash sites and things like that." she said.

"Perhaps those that were smaller in size were able to be more integrated into the small, densely packed communities. The ones that were smaller in size would be more accessible and easier to keep in the households or keep in pens outside."

Dr Gray says the research suggests that small dogs evolved early in the history of domestic dogs.

"It just gives us a greater understanding of the history of domestic dogs, being that they're a close companion animal, and how they've evolved to have this great amount of variation," she said.

"Not only do they exhibit a great amount of variation in body size, but they have other different characteristics such as different coat colours and coat types and things like that."

She says the study findings may be useful for dog breeders.

"It could potentially be used as a way to select for small body size, or it could be used to do cross-breeding between dogs to create a new breed, if breeders wanted to do such a thing," she said.